But Darius, when he came to that place in his march from Susa where the Bosporus was bridged in the territory of Calchedon, went aboard ship and sailed to the Dark Rocks1 (as they are called), which the Greeks say formerly moved; there, he sat on a headland and viewed the Pontus, a marvellous sight. [2] For it is the most wonderful sea of all. Its length is eleven thousand one hundred stades, and its breadth three thousand three hundred stades at the place where it is widest.2 [3] The channel at the entrance of this sea is four stades across; the narrow neck of the channel, called Bosporus, across which the bridge was thrown, is about one hundred and twenty stades long. The Bosporus reaches as far as to the Propontis; [4] and the Propontis is five hundred stades wide and one thousand four hundred long; its outlet is the Hellespont, which is no wider than seven stades and four hundred long. The Hellespont empties into a gulf of the sea which we call Aegean.